Airplane catapult



April 28, 1925.

C. F JEANSEN ET AL AIRPLANE CATAFULT Filed Feb 8. 1924 an a 6 Sheets-Sheet INVENTORS.

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F. JEANSEN ET AL AIRPLANE CATAPULT Filed FQb. 8, 1924 6 Sheets-Sheet 2 ATTORNEY.

C. F. JEANSEN ET AL AIRPLANE CATAPULT File Feb. 1924 6 Sheets-Sheeii 3 April 28, 1925. 1,535,475

7 C. F- JEANSEN 'ET AL I AIRPLANE GATAPULT Filed Q 1924 6 Sheets-Sheet 4 ATTORNEY.

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C. F. JEANSEN ET AL I AIRPLANE CATAPULT Filed Feb. 8. '1924 6 Sheets-Sheet 6 INVENTORS CarZ Z c azzsezzf fi ATTORNEY.

I I i\ Patented Apr. 28, 1925.

UNITED STATES 1,535,475 PATENT OFFICE.

CARL F. J'EANSEN AND ELMER F. STONE, OF WASHINGTON, DISTRICT OF COLUMBIA- AIRPLANE CATAPULT. I

Application filed February 8, 1924. Serial No. 691,441.

To all whom it may concern: Be it known that we, CARL F. JEANSEN and ELMER FLSTONE, citizens of the United States, residing at \Va'shington, in the District of Columbia, have invented new and useful Improvements in Airplane Catapults, of which the following is a specification.

This inventipn relates to catapults for launching airplanes from the decks of barges. ships, limited land'areas, or like restricted, spaces, and the main object of the invention is to provide means whereby the expansive'force of gases, produced by the ignition of an explosive, preferably gun powder, may be employed for communicating working motion to the airplane launching carriage in a-sa'l e, reliable and highly cllicient manner.

Another object of the invention isto provide means whereby the expansive force of the generated gases may be governed and controlled so as to avoid irregularities of motiOmshm-ks or jars, and so as to secure an easy and regulated motion of the launching carriage at the required rate of speed.

Still another object of the invention is to provide a catapult -which is simple of constrl'iction, which embodies a minimum number of workin! parts, which requires the services of a minimum. number of attendants, which may be constructed, operated and maintained in efiicient working condi-,

tion at a comparatively low cost, and by the use of which the operating power may beproduced in required amount only as needed at the moment of use, thus enabling storage tanks andother complex accessories for the storage and generation of power,

such, for example, as those used in compressed-air catapults, to be dis nsed with.

Still another object of the invention 15 to provide simple, re iable and efficient means for holding and releasing the airplane ata proper time period, and for properly tensioning the draft cable and setting the working arts in accurate relative positions for the 'aunching action. whereby smoothness and certainty of operation of the working parts will be obtained.

' In the accompanying drawings, showing one form of embodiment of the invention,'

Figure 1 is aside elevation of the catapult. i I

Figure 2 is a detail section through one sidle of the. carriage and one of the guide rar s.

Figure 3 is a vertical longitudinal sec tion through the explosion engine or power element of the catapult.

Figure 4 is a sectional plan view of the same.

Figure 5 is a transverse section on line 55 of Figure 3.

Figure 6 is a transverse section on line '66 of Figure 3.

Figure 7 is a sectional lan view of the carriage locking and releasmg and the draft cable tensioning device.

Figure 8 is a side elevation of the same, partially in section.

Figure 9 is a central vertical longitudinal section through the carriage locking and releasing and the draft-cable tensioning device.

Figure 10 is an end elevation thereof.

Figure 11 is a transverse sect-ion on line 1111 of Figure 9.

Figure 12 is an indicator diagram showing the ex )ansion chamber pressure in the travel of t e piston.

Figures 13 and 14 are views similar to Figures 3 and 4 of a modified form of explosion engine or power element.

Figure 15 is a transverse section on line 15-1-15 of Figure 13.

Figure 16 is a transverse section on line 16-16 of Figure 13.

Figure 17 is a view similar to Figures 4 and 14 disclosing the use of an expansion control valve.

Figure 18 is a section taken substantially on line 18'-18 of Figure 17.

action. This carriage is mounted to travel upon track rails 3 and is provided with slotted guide members 4 for enga ement with flanges 5 of the rails, whereby t e carriage slidahly mounted and held from vertical displacement. While a sliding type of is a section on line 20-20 of carriage is shown. a wheeled carriage may be employed, if desired. In practice, the rails...3 may be secured, to a. deck or; other rigid foundation orpto a turntable carried by such deck or foundation. Also in practice any suitable means may be used, if de-- sired or required, for locking the airplane to the car and releasing it at the launching moment, none being shown, as any of the devices commonly employed for the purpose ma be used.

rranged in working relationship to the carriage is a power mechanism comprising a cylinder 6 and a piston 7 working therein, The rod of this piston is coupled to a crosshead 8 movable on guide rails 9' extending between and carried by an exhaust chamber 10 and a stationary support 11, which support includes a bumper 12, of suitable type, and herein generally shown, for cushioning and arresting the outward motion of the piston 7 and cross-head 8. A draft cable 13 is fixed at one end to the carriage 1, passes around guide pulleys 14 and 15, suitably mounted upon the ship or other main structure, and is fixed at its opposite end to a lug or other projection 16 on the cross-head 8. A portion of this cable between the cross-head 8 and guide pulley 15 is looped and extended back and forth between and trained over gangs of motion multiplying pulleys or sheaves 17 and 18. respectively mounted upon the cross-head and a fixed part 19 of the structure, whereby motion transmitting mechanism is provided between the piston and carriage for driving the carriage at increased speed. The cable and pulley arrangement may be such in practice as to impart to the carriage an increased speed equal to twice the rate of speed of the piston, or any otherv degree of increase that may be required under dil ferent conditions of service.

The piston 7 is impelled on its working motion by the expansive force of gases generated from the ignition of an explosive charge, preferably gun powder. For the accomplishment of this object, an explosive engine comprising an explosion chamber 20 and an expansion chamber 21 are provided, said expansion chamber being arranged between and communicating at its opposite ends with the outlet end of the explosion chamber and inlet end of the cylinder 6, respectively. A breech n'lechanism and firing device 22, of suitable type, is provided for closing the mouth of the chamber 20 and firing thecharge inserted therein. lhe charge may be made. up of a primer surrounded by an ignition charge of black powder and the main charge of smokeless powder. preferably a slow burning powder such as used for large caliber guns. or any other slow burning explosive may be used. This charge may be. placed in a cartridge case so as to make it an easily handled unit. The charge is exploded in the explosion chamber and the gases expand to the proper pressure in the expansion chamber 21, from which latter they enter the working cylinder and act upon the piston, the piston being peripherally grooved or otherwise provided I with suitable means to prevent gas leakage. Under the force of the gases the piston 7 is moved forwardly in the cylinder-(i, there- 'ansmitting launching motion. to the carriage 1, when the latter is released for action, through the movements of the crosshead -8 and elements of the speed multiplying gearing, such motion being continued until the piston 7 uncovers the exhaust ports 3. A, suitable number of these ports 23 are provided in the cylinder 6 and communicate with the exhaust chamber 10, and this chamber 10 is provided, as particularly shown in Figure 5, with a pair of spaced chimneys or outlets 24 for the discharge of the exhaust gases to the atmosphere. At the limit of movement of the piston the crosshead 8 comes in contact with the cushioning bumper 12, whereby the. motion of the working parts is'arrested without shocks or jars. A cushioned stop or bumper 25 of approved construction may he arranged at the far end of the trackway J for similarly arresting the motion of the can riage l at the limit of its launching travel.

The function of the expansion chamber 21, which is always in direct open communication with the explosion chamber 20, is to automatically govern and control the expansion ot' the generated gases, and to maintain and insure the transmission to the piston 7 ot' a smooth and even working pressure, under substantially even driving power, throughout its range of movement. This is important in order to prevent disastrous shocks or jars on the working parts of the apparatus, which would otherwise occur. The dimensions of this expansion chamber are so chosen, relative to the dimensions of the bores of the explosion chamber and cylinder, that the gas entering the expansion chamber from the explosion chamber is confined and permitted to expand in the explosion chamber and attain a predetermined pressure below maximum pressure before acting on the piston in the working cylinder and to subsequently reach a predetermined maximum working pressure, which maximumworking pressure is substantially maintained to provide a substantially uni form working force on the motion transmitting mechanism during the launching travel of the carriage. the pressure on the piston being maintained with comparatively small loss until the exhaust. ports are uncovered. Figure 12 for example. the controlling action as exemplified by an indicator diagram, which shows the com mratively even and regular pressure maintained. with such variation oi pressure as unavoidably occurs in the expansion chamber due mainly to the cooling illustrates,

ltltl "of travelwofthepiston, the line A- C the gas pressure .ascent-line,1the line CD the gas:pressure-variation line in the travel of the.pistonyand the line DE the fall pressure line atwthetime ofjexhaust. At A the cliarge is fired, at B. the carriage is released,

shortly after firingiof'the charge, at (l the maximum pressureisireached, at D the exhaustiports area uncovered, and at E the piston stops.- The pressure curve line C-D indicates that through the controlling action onsthe gases established by the expansion of the gasesrqintogan iex ansion chamber of proper wdimensronsywt e 1 gas pressure is smoothly and evenly. maintained, wlth small -losses, principally?d ue to cooling, during the fu1l strokeof theipiston." As a result, the power!resultingv from the'force of the ex plosion 'will'be transmitted without shocks, jolts or "j ars, -'so that an even and regular ""tra vel of the laun'ching "carriage at a designated launching? speed 1 "is. obtained, The amount of the explosive charge employed is, ofcourse;governed by the Weight of the airplane and rat'eof launching speed which isto be transmitted and may be g v at will-according to these factors, so that an airplane ofany"size'and weight within the powerrang e e f-the launching apparatus as built ma'y "Alocking releasing mechanism is provided for locking the carriage 1 in starting position and automatically releasing it upon a determined pull on the draft cable 13, and

such mechanism also. serves as a means for in tially 'lacmg a proper tension on the draft cab e. Thls mechanism comprises a frame or carriage 26 provided with slotted coacting coupler link 31 on the car 1. The.

' latch 30 is adapted to be held in closed position by a spring-pressed, pivoted locking dog 32 havin an arm 33 provided with a locking tooth 34 to engage the free end of the latch30, and having a trip arm 35. The arm 35 engages and is movable in a guide slot in a relatively stationary trip member 36 having. V-shaped'trip or abutment surface 37. Thismember 36 is carried by a stem 38passing through an apertured lug 39. onthe frame26 and secured. in position by nuts 40, whereby the member 36 is adjustablyconnected with the frame 26 to set be launched with ease and facility."

rear face of the forward end or head 42 of the frame 26 is a coiled resistance and cushioning spring 43. Disposed also between the coupler head 29 and the front face of the head 42 is a cushioning spring 44, in .the form of a series of pairs of concave-convex spring disks, the concave surfaces of the disks of each pair being arranged to face each other. These springs 43.and 44 exertcounter pressures to normally maintain the coupler head 29 in properly spaced relationship to the head 42. The spring 43 serves to set up apredetermined yielding resistance, governed by adjustment of abutment 41, to the forward, carriage-releasing movement of the coupler head 29, under the pull of the draft cable 13. The spring 43 further serves to return the head 29 to: normal position after each froward movement thereof in a launching action, and as well as to cushion the forward motion of the head 29 under the pull of the draft cable up to the time of the carriage releasing action, while the spring 44 further serves to cushion and check the force of the rebound of the head 29 under the expansion of the spring 43; bothsprings mutually cooperating to prevent undue shocks or ars and possible damage to the parts of the locking and re-.

leasing device. A threaded tensioning rod 45, swiveled at its forward end to the rear end of the frame 26, extends through and engages with a stationary threaded stem or nut 46, and is provided With a hand wheel 47 whereby it may be rotated. By means of this stem the carriage 26 may be drawn rearwardly on the track rails 3 to set said carriage accurately in starting position andto place a proper tension upon the cable 13, in which operation the motor piston 7, through the action of the cable, is drawn backwardly and accurately set in starting position. 1 In the launching operation, the carriage is placed on the tracks 3 in its proper locationand locked-by engagement of the latch 30 with the keeper 31, the dog '32 being set to hold the latch 30, and the draft cable 13 is tensioned lay-adjustment ofthe stem 45. The airplaneis then placed in position on the carriage and the airplane engine started to drive the airplane propeller.

The cartridge is then placed in the gun and the breech mechanism closed and, when the airplane engine has reached full speed, the explosive charge is fired. The gases thereupon generatedfill the explosion chamber up to the piston, but, as a slow burning explosive is used, it requires an. appreciable time to reach the desired pressure. Before the full pressure has been reached, the pull upon the draft cable draws the coupler head 29 with its draw-bar 28 forwardly against the resistance of spring 43, Which is thereby compressed, allowing the coupler head 29 to have forward motion, in which action the dog 32 is retracted by the trip device 36, thus releasing the carriage 1 which moves forward on the launching action. The carriage with the airplane thereon thereupon begins to acquire speed, the speed being increased by the increase of gas pressureup to maximum, and through the speed multiplying motion of the power transmitting mechanism, whereby, as the carriage reaches the limit of its travel, a speed motion is transmitted thereto which may exactly equal or which may exceed to any desired extent the launching velocity, i. e., take-off speed, of the airplane. Shortly after the movement of the piston is arrested by its buffer, the motion of the launching carriage is arrested by the buffer 25, whereupon the airplane is released from the launching car and becomes airborne.

In Figures 13 to 16, inclusive, we have shown a modified form of the invention in which the expansion chamber 21' is arranged to partly enclose the piston cylinder 6, and in which the bumper 12 is mounted directly upon the head closing the outer end of the cylinder. In this modified construction, also, the cross-head 8' carrying the one. set of multiplying pulleys 17 is mounted for movement on the guides 9 which extend between the nested cylinder and expansion chamber and a support 19' which carries the other set of multiplying pulleys 18. The exhaust chamber 10 in this construction is also of slightly different form, having a single exhaust outlet or chimney 24. This construction provides a somewhat more compact type of apparatus which may be better suited for use under some conditions.

In Figures 17 to 21, inclusive, we have also shown a modified construction of apparatus which is generall similar to the or-- ganization illustrated in igures 1 to 6, inelusive, but embodies auxiliary means for governing the flow of the expanded ases from the expansion chamber to the wor ting cylinder. The means provided for this purpose comprises a small valve chamber 48 extending transversely. between the outlet end of the expansion chamber and inlet end of the power cylinder and provided with alined ports 49 communicating with said power chamber and cylinder. A piston valve 50 is mounted for movement in the chamber 48 to control the ports {19, and this valve is provided with a stem 51 extending externally through a stufiing box 52 and having mounted thereon a drum or pulley 53. The pulley 53 is journaled in a suitable support'54 through which the valve stem 51 extends and to which said stem is feathered so" as to hold it from rotation while permitting it to have sliding motion. The stem and hub of the pulley 53 are provided with engaging threads 55 whereby, through reverse rotary motions of the pulley or drum 53, back and forth sliding motion may be transmitted to the stem 51 and valve 50 for opening and closing the ports 49. A cable 56 is passed one or more times around a guide pulley 57 journaled on the support 11 and has its end portions fastened to the pulleyor. drum 53 so as to wind and unwind in reverse directions thereon on reverse movements of said drum.- ()ne stretch of this cable 56 is secured to an arnr58 projecting from the cross-head 8, so that, in the forward and backward travel of saidcrosshead, motion will be transmitted through the cable to the pulley or drum 53, to transmit opening and closing movements to the piston valve 50. By this means, when the cross-head moves outwardly on the nvorlting motion of the piston 7, the valve 50, which is always more or less open, i. e., never completely closed, will .be gradually and progressively opened to a fuller degree, so that when the pressure rises in. the expansion chamber the pressure will be simultaneously increased in the working cylinder, while on the return motion of the cross-head and piston said valve will be gradually and progressively closeda result the. flow of the gas pressure from the expansion chamber to the power cylinder will be automatically controlled to mathematically regulate the supply of the motive fluid for action on the piston so as tostill further reduce any tendency to pulsations or irregularities in the power flow, making it possible togovern the expansion of the gases and secure a desired smoothness of action of the working parts to such a degree as to entirely eliminate or render negligible any irregularities of flow tending to cause irregularities of motion of the launching mechanism.

The valve 50 is normally balanced with relation to the high pressure in chamber 21, but normally slightly unbalanced with relation to the relatively low pressure in cylinder 6, and, for the purpose of maintaining this unbalanced status, which assists in the operation of the valve, ports 59 are provided for connecting the ends of the valve chamber 38 with the adjacent end of the cylinder 6, which ports permit a portion of the gas-pressure contained'in cylinder 6 to pass into chamber 48 and to act on both ends of the piston valve 50, whereby the motion of said valveis assisted during the travel 'of the power piston, allowing a very sensitivegases and their action 011 the power mechanism such as our invention provides. By

the use of powder as the power agent, the

amount'of power to be developed for any launch ng action may be supplied and governed at will and produced at the time of use, obviating the necessity of employing storage tanks and other complicated equipment such as is necessary with launching apparatus employing other power producing agents, such as compressed air. The present invention not only provides a simplified form of apparatus for launching airplanes of all weights and sizes, but also one which may be installed and maintained in service at low cost, which occupies a mini-- mum amount of working space, and which may be easily handled and therefore requires the services of a comparatively small number of attendants.

In this specification and the following claims the term airplane is intended to cover any type of flying machine.

Having thus fully described the invention, what is claimed as new is:

1. In an airplane catapult, the combination of a track, a launching carriage adapted to travel on the track, an explosion device for producing expansive gases from a slow burning -explosive, mechanism for utilizing and transmitting the force. of the gases for propelling the carriage, and means operating automatically for permitting the gas to expand andattain a predetermined pressure below maximum pressure before action on said motion transmitting mechanism and to reach a subsequent maximum pressure and for thereafter maintaining a substantially uniform pressure and working force on the motion transmitting mechanism during the launching travel of the carriage.

2. In an airplane catapult, the combination of a track, a launching carriage adapted to travel on the track, an explosion device a for producing expansive gases from an explosive, means for controlling the expansion of the gases, and mot-ion transmitting mechanism for utilizing and transmitting the force of the controlled gases for propelling the carriage;

3. In an airplane catapult, the combination of a track a launching carriage adapted to travel on the track, an explosion device for producing expansive gases from an exmotion transmitting 4 plosive, motion transmitting mechanism operated by the expansive forces of the gases for propelling the carriage, and means between said explosive device and motion transmitting mechanism for securing controlled expansion of said gases.

4. In an airplanecatapult, the combination of a track, a launching carriage adapted to travel on the track, means for producing expansive gases from a slow burning'cxplosive, means for governing the expansion -of the gases, and means for transn'iitting the force ot' the expanding gases for propelling the carriage.

5. In an airplane catapult, the combination of a track, a launching carriage adapted to travel on the track, motion transmitting means, including a cylinder and piston, for

and conducting the same to the cylinder for action on the piston.

6. In an airplane catapult, the combination of a member for transmitting launching motion to the airplane, a chamber adapted for the firing therein of a slow burning explosive, a member adapted to be impelled by the force of the gases generated from 'the explosive, means disposed between said chamber and member for confining and permitting a predetermined expansion of the generated gases before action on the secondnamedmember, and means for transmitting motion from the second-named member to the first-named member.

7 In an airplane catapult, the combination of a track, a launching carriage adapted to travel on the track, a draft cable connected with the carriage, motion transmitting mechanism, including a cylinder and piston, for transmitting motion to the draft cable, an explosion chamber for the firing thereinof an expansive charge, and means between said chamber and the cylinder for controlling the expansion of thegases from the charge.

8. In an airplane catapult, the combination of a track, a launching carriage adapted to travel on the track, a draft cable connected with the carriage, motion transmit: ting mechanism, including a cylinder and piston, for transmitting motion to the cable, anexplosion chamber for the firing of an expansive charge therein, and an expansion chamber disposed between said explosion chamber and the cylinder for permitting a determined expansion of the gases resulting from the firing of the charge.

9. In an airplane catapult, the combination of a track, a launching carriage adapted to travel upon the track, a draft cable connected with the carriage, sets of speed multiplying pulleys around which the cable is passed, means including a cylinder and pision for transmitting motion to the cable, an

- propelling the explosion chamber adapted for the firing of an explosive charge therein, and conducting means between said chamber and the cylinder operative for securing a controlled expansion of the gases from the exploded charge.

10. In an airplane catapult, the combination of a track, a launching carriage adapted to travel on the track, two relatively fixed and movable sets of speed multiplying pulleys, a movable cross-head carrying the movable set of pulleys, a draft cable passing around the pulleys and terminally connected with the carriage and cross-head, means for transmitting motion to the cross-head including a cylinder and piston, an explosion chamber for producing an expansive gas charge for admission to said cylinder, and an expansion chamber for regulating the expansion and pressure of the gas charge disposed between the explosion chamber an the cylinder.

11. In an airplane catapult, the combination of a track, a launching carriage adapted to travel on the track, a draft cable connected with the carriage, a movable power member for transmitting motion to the cable, means for producing expansible gases from an explosive charge for action on said power member, and means for governing the expansion of the gases prior to the action thereof on said ower member.

12. In an airp ane catapult, the combination of a track, a launching carriage adapted to travel on the track, a draft cable connected with the carriage, a power element for transmitting motion to the cable, means for producing expansible gases from an explosive charge for action on said power element, and means for controlling the expansion of the gases.

13.- In an airplane catapult, the combination of a launching carriage, power mechanism, including a power element, for trans mitting motion to the carriage, an explosion chamber for producing expansible gases from an explosive charge for action on said power element, and means disposed between said explosion chamber and power element for governing the expansion of the gases.

In an airplane catapult, the combination of a track, a launching carriage adapted to travel on the track d'raft mechanism for carriage, an explosive engine for actuating the draft mechanism, and means for governing the expansion of the gases generated by said engine so as to secure an even and regulated application of the force thereof to said draft mechanism.

15. In an airplane catapult, the combination, with a launching carriage, and means for propelling the same, of locking and releasing mechanism for the carriage comprising a'shiftable support, a movable drawhead carried by said support, latch mecha-' ing a frame member,

.for propelling the same, of a locking and releasing mechanism for the carriage comprising a frame member, a movable drawhead carried by the frame member, a latch device carried by the draw-head for engagement with the carriage, an independently 'pivoted dog for holding said latch in latching position, means for yieldingly resisting forward motion of the draw-head and for returning the same; after forward motion and release of the latch device, to normal position, and a trip device for releasing the latch dog upon a predetermined forward movement of the draw-head.

17. In an airplane catapult, the combination, with a launching carriage and means for propelling the same, of lockingiand releasing mechanism for the carriage comprisa slidingdraw-bar carried by the frame member, a tripable latch mechanism carried by the draw-bar for engagement with-the carriage, springs arranged to respectively yieldingly oppose forward and backward movements of the draw-bar, and a trip device for releasing the latch mechanism upon a predetermined forward movement of the draw-bar under the pull of the carriage. 1

18. In an airplane catapult, the combination of a track, a carriage arranged to travel upon the track, power mechanism for propelling the carriage including a draft cable connected therewith, a frame movable upon the track, a resiliently mounted draft bar carried by said frame, latch mechanism carried by the draft bar for engagement with the carriage, means for releasing said latch mechanism upon a predetermined forward movement of the carriage and draft bar under pull of the cable, and means for adjusting the movable frame to impose a desired tension on the cable.

19. In an airplane catapult, the combination of a track, a launching carriage mounted to travel on the track, a power mechanism for propelling the carriage including a cylinder and piston, a draft cableconnecting said power mechanism with the carriage,'a frame slidably engaging the track. a spring restrained sliding draw-bar mounted on the frame, latch mechanism carried by the drawbar to engage the carriage, a trip device for releasing the latch mechanism upon a predetermined forwardmovement of the carriage and draw-bar under pull of the cable,

and means for adjusting the sliding frame on the track. y I

20. In an airplane catapult, a carriage locking and releasing mechanism comprising a support, a spring-controlled sliding drawbar on the support. a pivoted latch hook carried by the draw-bar, an independently pivoted dog for holding said latch hook in engaging position, and an adjustable "trip device normally fixed from movement relative to the draw-bar for retracting the dog upon a predetermined forward movement of the carriage and draw-bar.

21. In an airplane catapult, the combination of a track, a launching carriage adapted to travel on the track, a draft cable connect-' ed with the carriage, motor mechanism for actuating the draft cable, and a locking and releasing mechanism for the carriage comprising a frame, a movable draw-bar on the frame, counteracting springs for normally resisting forward and backward movements of the draw-bar, carriage locking means carried by the draw-bar, and a trip device for releasing said locking means on a predetermined forward movement of the carriage and draw-bar.

22. In an airplane catapult, the combination of a track, a launching carriage adaptautomatically governing the expansion and applied pressure of the gases. during the range of the launching motion so as to avoid charge of a slow burning explosive, a receiver for collecting and confining the gases from such slow burning explosive, saicl receiver operating to control the expansion of the gases evolved from the slow burnin explosive so as to provide for a regulate and substantially uniform application of thepower thereof Without material irregularities or fluctuationsduring the expansion period, and means operated by thecontrolled gases for transmitting the power thereof for a launching action to an airplane to be launched.

25. In an airplane launching apparatus, the'combination of an airplane launching carriage, an explosion chamber for the ignition therein of a slow burning explosive, motion transmitting mechanism coupled to the carriage, an expansion chamber between the explosion chamber and motion transmitting mechanism adapted to receive the gases resulting from the burning of the explosive and permit of the accumulation of the gases therein until a predetermlneq maximum working pressure thereof is reached, a carriage anchoring device, and yielding, releasable coupling means between the anchoring device and carriage operative upon a predetermined preliminary pull from the forces of the gases upon the carriage, and beforethe full working pressure of the gases in the expansion chamber is reached, to release the carriage from said anchoring device.

In testimony whereof we affix our signatures.

CARL F. JEANSEN. ELMER F. STONE. 

